I am rendering an image of a grotty old looking light-bulb. I can make a decent clear glass material, but, not a perfect one.

I simply cannot get the dirt textures to overlay properly.

How can I add dirt to my glass shader without ruining the glass material underneath it.

There is also an emission shader on the filament inside the bulb.

I tried looking for tutorial but they are all based on non transparent materials.


You can try adding a scratches map to your glass material. A quick Google search for "scratch bump map" can lead to some good results.

For the nodes, I would suggest two Glass BSDF shaders, one with 0 roughness and one with 0.4 roughness, run into a Mix Shader (0.4 Roughness one in top shader input). Use the image as a fac in the Mix Shader. You can add a Bright/Contrast node between the Image Texture and the Mix Shader. Adjust the Bright: value to affect the roughness.

Unfortunately, I can't post screenshots right now.


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.